Same developement time for 35 mm and 120 mm?

OMU · Apr 9, 2009

I have been testing my E.I for FP4+, HP5+, Delta 100 and Delta 400 with my Leica and Hasselblad. (Using HC 110 in Jobo)

FP4+ has an E.I at 80 both with my Leica (35mm) and my Hasselblad (120 mm). I have tested and found development time for N, N+1 and N-1 for the film exposed with the Leica. (35 mm)

I suppose I dont have to test the development times for the 120 mm?
Thanks.

Christopher Walrath · Apr 9, 2009

Wirelessly posted (BlackBerry9000/4.6.0.167 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/102 UP.Link/6.3.0.0.0)

For TMax films, 135 and 120 have identical developing times. You could consult Ilford publications o even the massive dev(elopment) chart to be sure.

rossawilson1 · Apr 9, 2009

Just make sure you use more juice to cover the film, but same times.. indeed they are!

ic-racer · Apr 9, 2009

I agree with the others that I have found contrast index to be very similar between film sizes. I have ascribed the small differences may arise from different technique. For example, if you only process a single 120 roll in a tank in which you process two 35mm rolls, the 120 may have a greater CI.

OMU · Apr 9, 2009

Thanks! As I thought.
Would it be the same for my 4" x 5"?

Christopher Walrath · Apr 9, 2009

Generally 4x5 films require slightly more development than their smaller format counterparts. The most reliable source for info is still going to be your film manufacturer's literature. After that one's own experiences can personalize it somewhat.

ic-racer · Apr 9, 2009

Maybe PE knows more, but the 4x5 Kodak film is thicker then the rollfilm. So, its not all cut from the same sheets or batches. Also, 4x5 is usually processed with a different method than rollfilm. Having said all that, my 4x5 T-max in an Expert Drum gives me about the same contrast index as T-max rollfilm in the 1500 drums, when using identical development times.

OMU · Apr 9, 2009

OK, I'll start with finding the development times for 35 mm and 120 mm and then do some testing for my 4" x 5" later. But from what you tell me, il expect times not far from what I’ve got from the smaller formats.

srs5694 · Apr 9, 2009

Incidentally (and in an admittedly nit-picky way), the film format you're calling "120 mm" is just "120" (or "120 format"). There's nothing about it that measures 120mm, unless perhaps you measure two 6x6 frames. It's actually 60mm across. The "mm" designation does belong with 35mm film; or it can be referred to as 135 film (but not 135mm).

Weird and inconsistent, I know -- but hey, this is a field in which 4x5 format is bigger than 6x6 format!

ic-racer · Apr 9, 2009

srs5694 said:
-- but hey, this is a field in which 4x5 format is bigger than 6x6 format!

...and 6x6 is way bigger than 8 x 11 !

Same developement time for 35 mm and 120 mm?

Privacy & Transparency

Privacy & Transparency